Hitherto, magnesium chloride and magnesium alkoxides have been widely used as a support material without being milled in the field of catalysts for olefin polymerization, specifically the homopolymerization or copolymerization of ethylene, propylene or the like. This may improve the catalyst activity and the morphology of polymer powder.
For example, for improving an obtained polymer in morphology including particle size, form, etc., there are known a method in which a magnesium compound is supported on an inorganic oxide such as silica (JP-A-S63-280707) and a method in which a magnesium compound once dissolved in a solvent such as an alcohol is precipitated again and the precipitate is used (JP-A-S56-000811). However, these methods include very complicated steps, since they require the procedures of supporting, dissolving and precipitating a magnesium compound. Further, these methods have a defect in that the catalyst is poor in performance stability.
The method of using as a support of catalysts a magnesium compound obtained by reacting metal magnesium, an alcohol such as ethanol and a certain amount of halogen (JP-A-H4-130107) has been developed. However, it has a problem in the point that the size and form of the polymer powder particle obtained depends on the conditions. For example, it does not permit omission of a pelletizing step and may not enable a copolymer of ethylene to be produced with sufficiently high efficiency.
In view of the above-mentioned problems, an object of the invention is to provide a magnesium compound, solid catalyst component and catalyst for olefin polymerization that exhibits high activity and can give an olefin polymer excellent in morphology of the polymer powder with a high stereoregularity.
Further, an object of the invention is to provide a method of producing an olefin polymer that can give an olefin polymer excellent in morphology of the polymer powder with a high stereoregularity.